1. Improper cooling water temperature.
2. Fouling in heat exchangers.
3. Crystallization.
4. More chilled water flow rate.
5. Insufficient steam pressure.
6. Air leakage and improper vacuum.
Absorption Chillers: Maintenance methods on absorption chillers are similar to those applied to boilers and centrifugal chillers. First, condenser and absorber tubes should be cleaned annually. Since these heat exchangers are in an open circuit—water passes through the absorber, on to the condenser and finally to the cooling tower, which is typically outside and open to the atmosphere—they are much more susceptible to contamination. Further, dirt in one part of the system contaminates the whole system. Annual cleaning of the condenser and absorber is essential for proper operation of the absorption cycle. A majority of problems in absorption machines are caused by dirty tubes in the absorber and condenser bundles.
Absorption machines also have a number of service valves which contain rubber diaphragms. These service valves perform a variety of functions. Their life cycles are typically three to five years. These valve diaphragms are often the source of air leaks in absorption machines. The removal of the lithium bromide/water charge from the machine every three to five years and replacing these rubber diaphragms is recommended. Removal of the charge also affords an opportunity to examine the solution and refrigerant pumps for wear and tear. It is very important not to introduce air into the machine during
